Method of combating nematodes



3,085,928 METHGD F CGMBATING NEMATGDES Arnold Hansweiler,Cologne-Flittard, Bernhard Honieyer, Gpladen, Karlheinz Legrand,Lever-kusen, and Klaus Schwarzer, (Iologne-Flittard, Germany, assignorsto Farbenfabrilren Bayer Aktiengesellschaft, Leverkusen, Germany, acorporation of Germany No Drawing. Filed Sept. 15, 1959, er. No. 840,021(Ilairns priority, application Germany Sept. 16, 1958 7 Claims. (Cl.167-42) The present invention relates to and has as its objects a methodof combating nematodes and new and useful nematicidal compositions. Thenew compositions consist of mixtures of 1.4-dichloro-butene and otherchlorinated lower hydrocarbons containing 3 or 4 carbon atoms.

The occurrence of phytophathogenic nematodes on our cultivated plants inhorticulture and agriculture is, in general, the result of intensecultivation. If this individual, mainly specific host plants areconsecutively cultivated in too short intervals the population ofnematodes increases to such an extent that they may cause deficienciesor reduced yields. Very efiective counter-measures are provided bysuitable crop rotation, that is to say, to cultivate the host plantswhich may be infected on the same soil in intervals of several yearsonly, Where this is impossible for economical reasons a direct combatingof the nematodes in the soil cannot be avoided.

Combatting nematodes with, inter alia, ethylene dibromide, mixtures of1.3-dich-loropropene and l.2-dichloro propane, or 1.4-dichlorobutene, isknown. P-ure 1.4-dich'lorobutene has, however, the disadvantage that itstays very long in the soil thus involving a very long refraining periodfrom cultivation.

In accordance with the present invention it has now been found thatmixtures of 1.4-dichlorobutene and chlorinated lower hydrocarbons from 3to 4 carbon atoms are very suitable for combating nematodes.

These chlorinated lower hydrocarbons containing 3 to 4 carbon atoms aree.g. 2.3-dichloropropene, 1.2-dichloropropane, l.2-dichloropropene-(1),l.1.2.3.3-pentachloropropane, 1.2-dichlorobutane, 2.3-dichlorobutane,2.4- dichlorobutene-(2 3.4-dichlorobutene-(1), 1.2.3-trichlorobutane or2.2.3-trichlorobutane. The aforementioned compounds, however, should notlimit the scope of the present invention in any way.

The compounds mentioned before do not have a nematicidal action per seor this action at least is very low. The mixtures with 1.4dichlorobutene, however, are nematicidal compositions which exhibit avery remarkable activity, compared with the components of the composition.

In general, good results are obtained by using mixtures containing to60% by weight of 14-dichlorobutene and 40 to 90% by weight of theaboveisaid chlorinated hydrocarbons, although, in some cases othermixing ratios are also applicable. The mixtures according to thisinvention, compared with the pure 1.4-dichlorobutene have the advantageof a better plant tolerance. The eifect of the latter is that inpractice the necessary refraining pe 3,085,928 Patented Apr. 16, 1963 2.riods from the application of the nematicide to the soil until theperiod of planting can, in some cases, be appreciably reduced. Thisadvantage is of great importance especially in intense cultivation,chiefly in horticulture.

The following examples ahe given for illustrating the present invention:

Example 1 Soil taken from fields and infested with nematodes indicatedbelow was treated in Mitscherlich pots of 5 litres capacity withstaggered quantities of the compounds indicated below. The pots infestedwith Meloidogyne incogniza were kept in a green house at 25 C., theother pots in the open air and uncovered. After a refraining period of 3weeks tomatoes, carrots, sugar beets and barleywere planted or sown. Theevaluation of the roots as to infestation by nematodes was carried outsix weeks later. The table shows the lowest quantities at which nonematode infestation is recognizable.

For testing the plant tolerance or ascertaining the necessary refrainingperiod from cultivation 12 square metreallotments were treated in each"case with respective quantities of 10, 20, 30, 40 and 50 cc. of thepreparation at 9 injection points per square metre. The soil used wasmedium weight sandy clay soil. The soil temperature in 5 m. depth duringthe tests varied between 12 and 18 C. Lettuce and carrots were sown 1and 3 weeks after treatment of the soil. The evaluation of plant growthwas carried out in each case after 4 weeks of sowing. The followingscheme served for the evaluation:

2 means normal plant growth 3 means slight damage to plant growth 4means strong damage to plant growth 5 means very strong damage to plantgrowth.

20 com] m3 Lettuce after 1 week:

ethylene dibromide 1.4-dichlorobutene. 2.3-dichlorpropene mixture of 15%1.4-dichlorobutene and 85% 2.3-dichloropropone mixture of 50% l.3dichloropropene and 50% 1.2-dichloro ropane eontro Lettuce after 3weeks:

ethylene dibromide- 1.4-diehlorobutene 2.3-dichloropropene mixture oi15% 1.4- ehlorobuteno and 85% 2 chloropropene mixture of 50%1.3-dlchr0propene and 50% 1.2-diehloropropanc control--.

Carrots alter 1 week:

ethylene dibromide 1.4-diol1lorobutene 2.3-dichloropropenemixture of 1 4chlorobutene and 85% 2. chloropropene. mixture of 50% dichloropropeneand 50% 1.2-diohloropropane control Carrots after 3 weeks:

ethylene dibromide l.4-diohlorobutcne.--. 2.3-dichloropropene NM N NM NMN [OM03 ION) NJ M0307 MM [O Nut mixture of 15% 1.4-dieh1orobutene and85% 2. v 1- chloropropene mixture or 50% 1.3-diehloropropeno and 50%1.2-dipropane" control.-.

The examples show that the mixture according to the invention requiresan essentially shorter period of retraining from cultivation than theknown preparations, even at low soil temperatures.

Example 3 The testing of the following mixtures for nematicidal activityhas been carried out using Meloia'ogyne incognita as testing species ofthe nematodes. 5 litres of infested soil each in Mitscherlich pots aretreated with various doses of the test mitxure and after a refrainingperiod of 1 week tomatoes are plantedthereon. Evaluation occurred after4 weeks by checking the results of the plants for cysts. In thefollowing table the lowest amount of inventive mixture is to be seenwhich gives suitable protection against attack by nematodes. As to theplant tolerance no mixture led to a damage under 300 p.p.m.

Minimum amount for killimg of Mixture ofnematodes in p.p.m.

12.5% 2.3-dichloropropene-(1) I less than 40.

30% 3.4dichlorobutene- (1)-.. 45% 1.4-dichlorobutene-(l).. 50%2.3dichloro ropene(1) 3.4-dichloro utene-(l) 1.4diehlorobutene-(2) 75%2.3-diehloro r0pe11e(1 10% 3.4-dichloro utene(1) 15%1.4-diehlorobutene-(2) 75% 1.1.2.3.Wpenta-chloropropane. 10%3.4-dichlorobutene-(1) 15% l.4-dichlorobutene(2)- 20% 1.2-dichlorobutenel l 5355;; l l l less than 40.

20% 2.3-d1c lorobutane 60% 1.4-dichlorobutene(2) 40% 1.23trichlorobutene 50 60% 1.4-dieh1orobutene- (2) .4-dichlorobutene-(2)16.5 tetra-chlorobutane 13.5% other chlorinated butanes and butenes (thecomplete mixture is the crude chlorination mixture of the butodienechlorination).

30 com./ 40 com./ 50 com./ In. m. m.

We claim:

. 1. Method of combating nematodes which comprises treating soil withmixtures of 10 to 60% 1.4-dichlorobutone and 40 to of a member selectedfrom the group consisting of a chlorinated alkane having from 3 to 4 carbon atoms and a chlorinated alkene having from 3 to 4 carbon atoms.

2. A nematicidal composition consisting of a mixture of 10 to 60%1.4-dichlorobutene and 40 to 90% of a member selected from the groupconsisting of a chlorinated alkane having from 3 to 4 carbon atoms and achlorinated alkene having from 3 to 4 carbon atoms.

3. Method of combating nematodes which comprises treating soil withmixtures of 10 to 60% 1.4dich1orobutene-(Z) and 40 to 90%2.3-dichloropropene-(1).

4. Method of combating nematodes which comprises treating soil withmixtures of 10 to 60% 1.4-dichlorobutene-(Z) and 40 to 90% of a mixtureof 3.4 dichlorobutane-(l), 2.3dichloropropene-(1) and1.2-dichloropropene-( 1 5. Method of combating nematodes which comprisestreating soil with mixtures of 10 to 60% 1.4-dichlorobutene-(Z), and 40to 90% of 3.4-dichloro-butene-(1) and dichlorobutane.

6. Method of combating nematodes which comprises treating soil withmixtures of 10 to 60% 1.4-dichlorobutone-(2) and 40 to 90% oftrichlorobutane.

7. Method of combating nematodes which comprises treating soil withmixtures of 10 to 60% 1.4-dichlorobutene-(Z) and 40 to 90% of3.4-dich1orobutene-( 1) and pentachlorobutane.

References Cited in the file of this patent UNITED STATES PATENTS2,411,566 Evan Nov. 26, 1946 OREIGN PATENTS 124,387 Australia June 12,1947 OTHER REFERENCES Agrl. Chemicals, November 1952, p. 39. Agrl.Chemicals, February 1956, p. 61.

1. METHOD OF CCOMBATING MEMATODES WHICH COMPRISES TREATING SOIL WITHMIXTURES OF 10 TO 60% 1.4-DICHLOROBUTENE AND 40 TO 90% OF A MEMBERSELECTED FROM THE GROUP CONSISTING OF A CHLORINATED ALKANE HAVING FROM 3TO 4 CARBON ATOMS AND A CHLORINATED ALKENE HAVING FROM 3 TO 4 CARBONATOMS.